Sound-producing mechanism



2 Sheets-Sheet 1 i QQ R @Q Aug. 7, 1923.

F.. B. LITTLE l SOUND PRODUCING MECHANISM Filed April 2, 1920 I' V Aug. 1, 1923. 1 1,464,156

` F. B. LITTLE 1 souN-D PRODUCING MEGHANISM f Filed April 2. 1920 Shoots-Sheet 2 Patented Aug. 7, 1923.

sTaTsjs i rieuse PATENT formen.

FREDERICK B. LITTLE, 0Fl CHICAGO, ILLINOIS, ASSIGNOE TO J. C. IDEAGAN, INC.,

0F CHICAGO, ILLINIS, A CORPORATION OF ILLINOIS.

SOUND-PRODUCING MECHANISIVI.

Application filed April 2, 1920. Serial No. 370,835.

To all whom z'zi may concern Be it known that l, FREDERICK B. LITTLE, citizen of the United States,'residing at Chicago, in thecounty of Cook and State of Illinois. have invented a certain new and useful Improvement in Sound-Producing lMech-anism` of which the following is a full, clear, concise, andexact description.

My invention relates to sound producing equipment and is of particular service when employed in percussion musical instruments refluii'ing heavy actions and has for its general obj ect the provision of an improved electrically operated action capable of properly r setting massive vibrant bodies into vibration.

The invention has. for a specific purpose the provi n of mechanism insuring the retention of the hammer of the action in its rearmost position so that the extent of the forward travel ofthe hammer is always uniform. being .in this respect an improvementI upon other electric actions in which the hammers are apt to come to rest in various restored positions forward of their rearmost- 5 restored positions.

The action of my invention further includes a housingfor the switching mechanism and havingin its formation the supiiorting base of the equipment.

Generally speaking, my .invention is real ized in a structure that is inclusiveof a vibrant element, a hammer mounted to strike said element to set it into vibration, and -..ro-magnetic mechanism having a strik winding for moving the hammer into striking engagement with said vibrant element and also desirably having a restoring winding for withdrawing the hammerl to initial positionA There is a striking relay having a switch cont felled thereby for opening and closing the circuit of the striking winding` The restoring winding is also preferably controlled by a relay having a switch controlled thereby for opening` and closinga the circuit of the restoring winding. rlhe equipment. according to the purpose to be served employs either or both a normally open switch and a normally closed switch. lilliere the normally open switch is employed it isilesirably in 'the circuit of the restoring relav and also connected to constitute the holding switch of an electro-magnet which is 'controlled from a keyboard or other suitable place. Where a normally closed switch is employed it is in the circuit of the striking relay. The aforesaid electro-magnet included in the equipment above described has an armature normally mechanically positioned to maintain the normally closed switch in its normal adjustment1 said magnet serving when energized to attract its armature to open said normally closed switch and to close said normally open switch. There is also switching mechanism that is placed in `i one adjustment by the hammer in being restored and then serving to connect the aforesaid normally closed switch in the circuit of the striking relay and serving in an alternative adjustment that is efected by the ham- Vmer in being moved to striking position to disconnect said normally closed switch from the striking relay and to close the circuitl of said magnet to open said normally closed switch and to close said normally vopen swi ch. said switching mechanism in its first aforesaid adjustment serving to open the magnet circuit where closed thereby in said alternative adjustment of the switching mechanism.

All of the electro-magnetic equipment of each action and the gong orchime to be operated thereby is desirably mounted upon a single base which is made in separable sections that hermetically enclose a space containing the switching mechanism thatis in control. of the electro-magnetic mechanism. y

I will explain my invention more fully by reference to the accompanying drawings showing the preferred embodiment thereof and in which Fig. l is a plan view of my improved electric action and a gong or chime to be operated thereby; Fig'. 2 is a sectional view on line 2 2 of Fig. l; and Fig@ is an electrical diagram illustrating the circuit lconnections of the equipment.

Like parts are indicated by similar' characters of reference throughout the different figures. v j v The vibrating element illustrated is in the form of a tubular gong or chime' 1 having `a bail 2 passing. diametrically through its Ylay upper end, this bail being carried by a hanger 3 adustable longitudinally of a suporting frame ai and held in adjustment by bolts t, The force with' which the; hammer 5 is applied to the vibrating element, in heavy actions, is sufficiently powerful to ef= feet a partial rebound of the hammer' from the vibrating elementfwhereby the vibrations which are set up therein are not dampened. The hammer is desirablyelectrically operated to effect both its striking and withdrawing movements and on this account' employ a striking winding 6 and a restoring winding 7 de'sirably forming the component solenoids or magnets of a double magnet-or compound Solenoid having a common iron cofreQS to be niag'netically actnatedbyV the windings, theQstrikinglcoil 6 operating to move the .core from its rea'rmost position when thehaminer 5 is't'o 'be' applied while th ,restoring coil 7 operates to place the core to ,etherv with thehiamni'e'r adjacent thereto in fully restored position. rlhe hammer andthe hammer stem 9 that couples ltheV hammer with the solenoid core are desirably A ,fc of brass, Vthe llni'inmer andits stem coupled by a pin 1'Othat is downwardly projected t`o,'be in actuating relation to the iiitermediately pivoted rocker ,ory switch arm liwhich is iniiiedrelation to a circuit clos'- ing Ablade 12 V,that is oscillated to correspond to the oscillating movementsoof the rockerV clockwise direction by the pin 10 just before the hammer 'strikes "the gong Vor chime, said rocker arm being brought to the reverse position illustrated when the hammer is vfully retracted. -Thus thjehammer when in striking movement closes 'one gap l2, 13, 15, in a infasterzrestoring circuit and in its withdrawing movement closes one gap 172, 13,14,

in a m ster striking circuitgthe i'nasterv cir cuitsv spectively including relays 16 and `vvhiclfi" are respectrfelyv restoring and 'strikingrelays; In the embodiment ofthe invention illil tratejd each pair of these re- ,r erniedvb'y a ley controlled switch, thereV being" illustrated a self-restoring piano key l18 governinga switch 19, 20 individual tothe rofi,relays 16,1)12and a testing switch 2 1`,'j22 inmultiple with switch 19, 20 and"positioned where the chime is located to be accessible to one adjusting the chime `a* striking switch which is individual to the striking relay 17,A the winding of said striking relay, to the negative pole of said` generator byv way of the closed contacts 19 'and 2O pertainingrto the `actuated key 18. The relays 16, 17 are desirably in the form of solenoids whose ,coresv respectively carry contac'ts 296,27, Then the striking relay is energizedvthe ContactV 27 fupon its core is en- 'gage'd'with the contact'28 constituting one terminal' of the winding 6 with the result that a hammerfoperating circuit is closed lfor imparting a striking movement to the hammer, such circuit being traceable from the positive pole of the generator 23, through the contacts 26, 27, the contact V28 engaged by theA contact 27, the striking winding 6, to

the negative terminal of the generator.

1Whe-n the striking winding is thus included in circuit the hammer is moved rapidly forward to `st1il{e`the gong'or chime 1, the hammer rebounding a slight distance and remaining in its rebounded position if the key 18, in thefneantimc, should happen to be released. VInasmuch asv it is usual to maintain the actuated.'` key depressed a su'iicient length of'time to bring thev apparatus to normal or idle` adjusti'nen't, circuits and circuit changes are brought about, when there is such continued depressionof said key, and upon the hammer 5 nearly reaching its'foremost positiomin arriving at which position the n 1Q causes counteicloclwise mm'ement the rocker arm 11 consequent upon en gagement of said pin with the left hand end of said rocker arm. The switch blade 12is consequently moved out of engagement with the bifurcated Vcontact 14 and into engagement with the contact 15 constituting one terminal `of a magnet 29. The circuit of winding 17 is thus brolen,allowing switch tion of the winding 6,.and another circuit is VsimultaneouslyA established traceable yfrom the positive v.pole of the generator 23, through the common conductor connecting this pole withthe common contact 13, thence vthrough the switch blade. 12, the contact 15` in advance of the hammer striking the chime that the magnet 29 is energized before the hammer reaches its foremost position,

the hammer being carried forward by :its

momentum. It will also be noted that immediately upon energizationof the magnet the armature 29 thereof, which is pivoted at 29', is attracted and as' a result the switch 31, 32 is closed and switch 2&1, 25 opened due to the inherent resiliency of. member 25.y The restoring relay 116, being now energized7 applies the contact26 upon the core thereof to the contact 29 and thereby closes the circuit of` the restoring solenoid winding 7 (into whose bore. the hammer core 8y extends) the circuit established by the engagement oi the contact26 with the contact 30 being traceable from the positive pole of the generator 23,through the contact 26, the Contact 30, the restoring winding 7, to the negative terminal of said generator. Upon energization of the solenoid 7 the hammer is retracted and when the same nears its rearmost position the pin 10 is brought into rocking engagement with the rocker arm ,11 to move the switchblade 12 in acloclrwise direction thereby to separate the switch blade 12 from the Contact 15, aseparation that would serve to open the circuit of the magnet 29 had not the attracted armature of this magnet caused the movement'oi. the contact 31 intoengagement with the contact 32, these latter contacts being respectively multiples et the contacts 13 vand 15 and therefore serving as a holding switch to maintain the circuit of magnet 29 closed after the switch blade 12 hasl been separated from the contact 15. `As consequence of the continued energization of themagnet 29 follow ing the separation ot the switch blade 12 from the Contact 15 'that occurs Abetere the hammer reaches its rearmost position, the

striking switch 211, remains opened so' that thev striking relay` 17` cannot be energized to engage its contact 27 with the contact 28, .it being understood that the key 18 still continues to be depressed in order to maintain the energization of the magnet 29 whose circuit includes the switch 19, 2O controlled by such key. .After the switch blade 12 has separated Jfrom the contact 15 it engages the bifurcated Contact 14C to connect 'the positive pole of the generator 23 with the striking switch contact 24 so that when the actuated key 18 is iinally'released ultimately to open the ,circuit of the magnet 29 yat the switch 19. 20, the armature ot said magnet will be released, this armature being desirably forcibly retracted by the retractile.,

retractive movement of the plete closure of this circuit when the key 18, individual to this striking relay is depressed with the results which have hitherto been described.

The switch 31, 32., in addition to co-operating with switch 19, 2O to maintain the magnet 29 energized. to keep the switch 2e, opened and the solenoid 7 deenergized to prevent ychattering movement of the hammer against the chime, also maintains closed the circuit of therestoring relay 16 with whose winding said switch 31, 32 is in series and inasmuch as the restoringvswitch 31, 32 is not opened by the hammer but'is only opened when the key 18 is released, the han mer may be yplaced in its fully withdrawn Y position providing the key 18 'is maintained depressed a su'liicient length of time.

It will bev observed that the winding 16 is energized by two circuits, one of which, that is, thecircuit including switch 12-,13-15, may be termed the main operating circuit of electro-magnetically operated switch 26, 30,7while the other, that is,` the circuit including switch 31, 32, may be termed aseoondary circuit therefor. winding 18 and the latter or secondary circuit is closed during retraction of the hammer and after the main circuit iS opened by hammer to thereby maintain the winding 16 energized and the hammer thereby retracted until the control switch constitutedvv by 19, 2O is opened. i f

It will bc further noted that the switch elements'31 and 32 when closed constitute with their continuing connections a shunt circuit which 'cuts in automatically when the main operating circuit of switch 26-30 is opened by retractive movement of the hammer to provide the closed secondary .operating circuit ot the switch 26-30 for separable portion 42 constituting a lid or closurefor the pocket 13 formed in the body ot the support, bolts 14 being employed to Both include the clamp the closure and the body portion of thesupport together. The support 'is dersirably made ot iron, the meeting edges of the closure with the marginal edges of the pocket 13 being accurately machined to have tight hermetic lit. The electro-magnetic equipment is desirably supported upon ther top or outer side oi, the closure 42 and the switching mechanism that controls such equipment is desirably confined within the pocket i3 to be thoroughly protected from the elements. rllhis switching mechanism is preferably' fastened to theinner side of the closure. y 1 y' y i YVhile l have :herein shown and particui larly described the preferred embodiment ot my invention l' donot wish to be limited to the' precise details or" construction shown as changes may readily be made without departing fromthespirit of my invention, but having thusl described my invention I claim asne'w and desire to'securc by Letters Patent thel following:

l. Sound producing mechanismV including f a -vibrant element, a ifrojectile and retract-- 'Y able hammer mounted lto strike said element to render said first named electro-magnetic `mechanism inactive and said second` name electro-magnetic mechanism active,V and rieansfor maintaining the activity oii'said second named electro-magnetic v mechanism until the,` control switch is opened.

2; Sound producing mechanism includiing a'vibr-ant element, a projectile, and re- Vtractalole 4hammer vmounted to strike said `elementwvhen projected, a control switch operable idependently of 'electro-magnetic force, normally inactive electro-magnetic mechanism for initiating projectioniof'the hammer includinga circuit, a normally open kelectro-magrietically closed" switch inl said circuit, an' operating circuitV tor said'elect'ro-V `magnetically operatedswitch including said control switch operable whenclosed to render` the hammer'projecting electro-magnetic .mechanism active, normally inactive electromagneticV mechanism for' retracting and holding said hammer retracted, means op- Vratedvbyihf? 5511211 'movement of Projection VVot the hammer to render ysaid first Ymungd electro-magnetic mechanism Vinactive' and said second named electro-magnetic mechanism active, and means for maintaining the activity of said Vsecond .named electro-magnetic mechanism until the control switch is openech l '3. Soi/ind'producing mechanism including fay vibrant'element, a projectile and retrac- Yeo 'table hammer inountedfto strike said vele-4 ment when projected, a control switch opfera'ble Vin'dep'endently of Veleetre-magnetic force, normally inactiveV electro-magnetic mechanism for initiating projection of the hammer," said `ele'otro-magnetic mechanism Vbeingrendered active-'by the closingof said control switch, normally inactive electromagnetic mechanismv for retr-acting K said hammer including 'a circuitya normally open electro-magnetically VAclosed switch in said circuit, an voperating circuit "for said electro-magnetically operated switch including the control switch, means operated by the hammer during its final movements ot projection and retraction to Vclose and open, re

spectively, the operating circuit of said elec'-V tro-inagnetically operated switch whenk the a circuit,'a normally open electro-magnetically closcd switch in said circuit, a main operating circuit for said Velectro-magnetically operated switch including the control switch, a shunt circuit, means operated by the hammer Vduring its final movements of projection and retraction to close yand open, respectively, :the `main Voperating `circuit of said electro-magnetically operated switch when the control switch isl closed',fand means `for maintaining the electro-magnetically. operated switch closed afterthe main operatingcircuit thereof is opened by the move- Vment ofthe hammer and until said control switch is opened, means vfor, cutting in Said shunt circuit during retraction of the hammerto provide asecondary closed operating circuit forthe electro-'magnetically operated switch until the control switch is opened.

5. `Sound producing mechanisml including 'a vibrant element, a projectile and retractable hammer mounted to strike said element when projected, a control switch, normally inactive electro-magnetic mechanism for initiating projection of the hammer,

dered active by the closing of'said control switch, normally inactive electro-magnetic of projection and retraction `to 'close and o- -en res ectivel Vthe main o eratin Acircuit of said electro-magnetically operated switch when the l/controlswitch is closed, electro-magnetically operated means included inthe main operating circuit of the 'electro-magnetically "operated: switch for closing the :switch device of lthe shunt cir-j fioA said electro-magnetic mechanism being rencuit to provide a secondary closed operating circuit for the electro-magnetically operated switch after its main operating circuit has been opened by retractive movement of the hammer and until the control yswitch is opened.

6. Sound producing mechanism including a vibrant element; a hammer mounted to strike said element to set it into vibration;

electro-magnetic .mechanism having striling Winding for moving the hammer' into striking engagement With said vibrant element and a restoring Winding for Withdrawing the hammer to initial position; a striking relay having a switch controlled thereby that is in the circuit of the striking Winding for rendering the striking Winding effective or non-edective; a restoring relay having a switch controlled thereby that is in the circuit Ot' the restoring Winding for rendering the restoring Winding effective or non-eitective; a normally open switch in thecircuit of the restoring relay; a normally closed switch in the circuit of the striking'relay; an electro-magnet controlling the latter tvvo switches and serving when energized to attract its armature to open said normally closed switch and to close said normally open switchv which is also in t-he circuit oft said magnet to constitute a magnet holding switch; a controlling switch in controlli-ng relation to said magnet; and switching mechanism placed in one adjustment by the hammer in being restored and then serving to connect the aforesaid normally closed switch in the circuit of the striking relay and serving in an alternative adjustment that is efiected by the hammer in being moved to striking position 'to disconnect said normally closed switch from the striking rela-y and to close the circuit oi" said magnet to open said normally closed switch and to close said normally open switch, said yswitching mechanism in its lirst aforesaid adjustment serving to open the magnet circuit Where closed thereby in said alternative ustment of the switching mechanism.

In Witness whereof, I hereunto subscribe my name this 26th day 01": March A. D., 1920.

' FREDERICK B. LITTLE. 

